package com.atguigu.gulimall.product.service.impl;

import org.springframework.stereotype.Service;

import java.util.Comparator;
import java.util.List;
import java.util.Map;
import java.util.stream.Collectors;

import com.baomidou.mybatisplus.core.conditions.query.QueryWrapper;
import com.baomidou.mybatisplus.core.metadata.IPage;
import com.baomidou.mybatisplus.extension.service.impl.ServiceImpl;
import com.atguigu.common.utils.PageUtils;
import com.atguigu.common.utils.Query;

import com.atguigu.gulimall.product.dao.CategoryDao;
import com.atguigu.gulimall.product.entity.CategoryEntity;
import com.atguigu.gulimall.product.service.CategoryService;

import javax.xml.bind.annotation.XmlEnum;


@Service("categoryService")
public class CategoryServiceImpl extends ServiceImpl<CategoryDao, CategoryEntity> implements CategoryService {

    @Override
    public PageUtils queryPage(Map<String, Object> params) {
        IPage<CategoryEntity> page = this.page(
                new Query<CategoryEntity>().getPage(params),
                new QueryWrapper<CategoryEntity>()
        );

        return new PageUtils(page);
    }

    @Override
    public List<CategoryEntity> listWithTree() {
        //1.查出所有分类
        List<CategoryEntity> entities = baseMapper.selectList(null);

        //2.组装成父子的树形结构
        //2.1 根据夫分类parentId找出所有一级分类
        List<CategoryEntity> levelMenus = entities.stream().filter(categoryEntity ->
                categoryEntity.getParentCid() == 0).map((menu) ->{
                    menu.setChildren(getChildrens(menu,entities));
                    return menu;
        }).sorted(Comparator.comparing(CategoryEntity::getSort))
                .collect(Collectors.toList());

        return levelMenus;
    }

    @Override
    public void removeMenuByIds(List<Long> list) {
        //TODO 1.检查当前删除的菜单，是否被别的地方引用

        //逻辑删除
        baseMapper.deleteBatchIds(list);
    }

    private List<CategoryEntity> getChildrens(CategoryEntity root, List<CategoryEntity> all) {
        List<CategoryEntity> children = all.stream().filter(categoryEntity ->
                categoryEntity.getParentCid() == root.getCatId()).map((categoryEntity) -> {
            categoryEntity.setChildren(getChildrens(categoryEntity, all));
            return categoryEntity;
        }).sorted((menu1,menu2) ->{
            // 菜单排序
            return (menu1.getSort() == null ? 0 : menu1.getSort()) - (menu2.getSort() == null ? 0 : menu2.getSort());
                }

        ).collect(Collectors.toList());

        return children;


    }

}